Takayama Minami--She's cool when she voices boys as for Conan!!Shiraishi Ryoko-She's the most important for the voice of Hayate for me..Hayashibara Megumi-My Queen of SeiyuusMinagawa Junko-I adore her captive skill on voice actingPaku Romi-She's the seiyuu,I've been interested on speaking Korean,although I cannot speak it~Hirano Aya-I like her for Konata..

Some of my favorite Seiyuu:
Mai Nakahara - Nagisa from Clannad; Zakuro from Otome Youkai Zakuro; many others;
Ami Koshimizu - Holo from Spice and Wolf; Leo-hime from Dog Days; many others;
Kikuko Inoue - Belldandy from Ah My Goddess; various "Hot Shoenen Mom" characters like Miyuki Azuki (Miho's mom) from Bakuman and Sanae (Nagisa's mom) from Clannad; Mizuho from Onegai Teacher; Rangui from Otome Youkai Zakuro; and many, many more - all that and she is only 17 years old!;
Aki Toyosaki - Fam from Last Exile: Fam the Silver Wing; Nako from Hanasaku Iroha; Yui from K-On!; a member of the idol group Sphere; and many, many more;
Aoi Yuuki - Victorique from Gosick; Madoka from Puella Magi Madoka Magica; Noel from So Ra No Wo To; and many, many more! (And she is such a little cutie! She is only about 1 inch taller than the character Victorique!)

and the newest member of my favorites list:
Ayako Yoshitani - Urabe Mikoto from Mysterious Girlfriend X - the most unique and sexy voice in anime!

English voice actresses and actors:
Brina Palencia - Holo from Spice and Wolf; Ryouko Ookami from Ookamisan; Natsuki Shinohara from Summer Wars; and many, many more! (She is a good singer too...)
J. Michael Tatum - Lawrence from Spice and Wolf; Sebastian from Black Butler; Kyouya from Ouran High School Host Club; and many, many more;
Luci Christian - Her list is in a post above this, but my favorite of her roles is Kaname Chidori from Full Metal Panic;
Chris Patton - Also for his work on Full Metal Panic as Sousuke Sagara among others.

So far I like Rie Kugimiya cause her tsundere voice is so moe and lately after I watch steins gate I also like Mamoru Miyano. Sorry for few names I dont really look into the voice actor/actress name unless I really like most of the character